Search results for "analytical"

Mineral profiles of legumes and fruits through partial least squares energy dispersive X-ray fluorescence

2019

Abstarct Energy dispersive X-ray fluorescence (ED-XRF) has been employed for the determination of mineral elements in 15 varieties of legumes and 14 cherry samples. ED-XRF signals directly obtained from pulverized samples were modelized by partial least squares (PLS) using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) of a selected number of samples, after microwave assisted acid digestion, as reference data. Models were built to predict the concentration of Al, Ca, Cu, Fe, K, Mg, P, Sr and Zn. Average concentrations predicted were 6, 930, 7, 40, 6400, 990, 2100, 4 and 15 μg g−1 for Al, Ca, Cu, Fe, K, Mg, P, Sr and Zn, respectively with relative errors from 7 till 26%. …

Problems in time-intensity measurements. A case study-Bitterness evaluation in water solutions and in beers

1992

International audience

Modeling of Particle Number Fluctuations in Entire Cells

2012

In a recent study we developed a method to model protein diffusion in cells [1], where special attention was given to generating from image data of the measured cell a realistic digital model cell in which protein dynamics were simulated. The method was shown to be well suited for modeling non-equilibrium situations that arise, e.g., in photobleaching experiments, and to be capable of producing more detailed information about protein motion than traditional modeling.Another experimental way to assess protein dynamics is to study fluctuations in the local protein number, as it is done, e.g., in fluorescence correlation spectroscopy (FCS), or in similar measurements that apply single-plane il…

2020

The transfer of metabolites through the mitochondrial membranes is a vital process that is highly controlled and regulated by the inner membrane. A variety of metabolites, nucleotides, and cofactors are transported across the inner mitochondrial membrane (IMM) by a superfamily of membrane transporters which are known as the mitochondrial carrier family (MCF) or the solute carrier family 25 (SLC25 protein family). In humans, the MCF has 53 members encoded by nuclear genes. Members of the SLC25 family of transporters, which is the largest group of solute carriers, are also known as mitochondrial carriers (MCs). Because MCs are nuclear-coded proteins, they must be imported into the IMM. When c…

genuMet: distinguish genuine untargeted metabolic features without quality control samples

2019

AbstractMotivationLarge-scale untargeted metabolomics experiments lead to detection of thousands of novel metabolic features as well as false positive artifacts. With the incorporation of pooled QC samples and corresponding bioinformatics algorithms, those measurement artifacts can be well quality controlled. However, it is impracticable for all the studies to apply such experimental design.ResultsWe introduce a post-alignment quality control method called genuMet, which is solely based on injection order of biological samples to identify potential false metabolic features. In terms of the missing pattern of metabolic signals, genuMet can reach over 95% true negative rate and 85% true posit…

« Nez et langues électroniques » : bilan et perspectives pour les huiles alimentaires

2003

Le « Nez electronique », et plus recemment la « Langue electronique » ont ete fort mediatises durant la derniere decennie. Aussi est-il necessaire, avec le recul, de faire le point sur les benefices que ces technologies peuvent apporter dans le domaine des produits alimentaires, et en particulier pour huiles vegetales. On trouve une litterature relativement abondante dans ce domaine, mais les applications qui ont reussi a franchir le cap de l’utilisation industrielle sont extremement restreintes. S’agit-il d’une frilosite des industriels pour des investissements de controle-qualite ou d’un manque de fiabilite des resultats de laboratoire ? Pourtant, la demande en outils rapides de controle-…

Electrochemical modifications of proteins: disulfide bonds reduction

2002

International audience; Electrochemical reduction of lysozyme disulfide bonds was achieved at pH between 10 and 11.Below pH 10, no disulfide bond cleavage was observed. At pH higher than 12, the cleavage of disulfide bonds is essentially due to hydrolysis. The addition of denaturant considerably enhanced the performance of the electrochemical device.

Salt and Aroma Compound Distributions Influence Flavour Release and Temporal Perception While Eating Hot-Served Flans.

2021

International audience; To counteract the negative effect of salt overconsumption on health, strategies have been developed to reduce the salt content in food products. Among them, two promising strategies based on odour-induced saltiness enhancement and the heterogeneous distribution of flavour compounds were combined and assessed in four-layer cream-based snacks. To investigate the relationship between saltiness enhancement, temporal release and perception of flavour compounds in hot snacks with heterogeneous distribution of salt and aroma compounds, complementary techniques were used: nose space PTR-Tof-MS (Proton Transfer Reaction-Time of Flight–Mass Spectrometry) to assess the release …

Physicochemical properties, sugar profile, and non-starch polysaccharides characterization of old wheat malt landraces

2021

Abstract Craft beers produced by small breweries are becoming increasingly popular worldwide due to their unique composition, taste, and flavour. Wheat malt is a traditional brewing raw material with great potential to improve beer properties such as mouthfeel, foam, haze, and flavour. In this study, the malting quality of eight wheat varieties (four common and four durum) was evaluated to explore the feasibility of producing 100 % wheat malt beer from old landraces. The physicochemical characteristics such as friability, Kolbach index, viscosity, and colour, of the wheat malts indicated a better degree of modification in the common wheat varieties when compared to that of the durum wheat v…

Validation of Using Smartphone Built-In Accelerometers to Estimate the Active Energy Expenditures of Full-Time Manual Wheelchair Users with Spinal Co…

2021

[EN] This study aimed to investigate the validity of using built-in smartphone accelerometers to estimate the active energy expenditures of full-time manual wheelchair users with spinal cord injury (SCI). Twenty participants with complete SCI completed 10 5-min daily activities that involved the upper limbs, during which their oxygen consumption and upper limb activity were registered using a portable gas analyzer and a smartphone (placed on the non-dominant arm), respectively. Time series of 1-min averaged oxygen consumption and 55 accelerometer variables (13 variables for each of the four axes and three additional variables for the correlations between axes) were used to estimate three mu…